Tissue removal surgery is frequently assisted by navigation technology to guide the surgical procedure in real time. For example, a biopsy may be guided by ultrasound imaging to ensure that the biopsy is performed at the required location, or removal of the intervertebral disc from a spinal segment may be guided by fluoroscopic x-ray guidance to avoid damaging the spinal cord or nerve roots. Cancer-related tissue removal procedures generally require particularly high accuracy. When performing a biopsy of tissue suspected to be cancerous, proper diagnosis relies on sample retrieval from tumor, hence from a specified location, not from nearby normal tissues. When surgically removing a tumor, any cancerous tissue inadvertently left behind may be detrimental to the patient.
Traditionally, breast tumor resection is guided by a wire penetrating the breast to reach the tumor or a radio-opaque clip placed within the tumor. Breast tumor resection is the removal of the cancerous tissue only, as opposed to removal of the whole breast. The radio-opaque clip may be placed in the tumor during a biopsy procedure. The wire insertion is guided by imaging, for example ultrasound imaging, magneto resonance imaging (MRI), or mammography. It is challenging to ensure that the entire perimeter of the tumor is removed including any filaments or fimbriae. Frequently, since some cancerous tissue remains in the breast after the resection surgery, breast tumor resection is usually accompanied by radiation treatment with the intent of destroying any unremoved cancerous tissue. Nevertheless, about one in four women having undergone breast tumor resection need to return for further resection of cancerous tissue at or near the site of the original resection.